Debt (Details) € in Millions				12 Months Ended
	Sep. 12, 2019 USD ($)	Apr. 11, 2018 USD ($)	Jul. 19, 2016 USD ($)	Jan. 03, 2021 USD ($)	Jan. 03, 2021 EUR (€)	Dec. 29, 2019 USD ($)	Dec. 29, 2019 EUR (€)	Sep. 17, 2019 USD ($)	Jul. 19, 2016 EUR (€)
Unamortized discount and debt issuance costs				$ (18,305,000)
Maturities of Long-term Debt [Abstract]
2017				381,193,000
2018				4,075,000
2019				2,457,000
2020				159,967,000
2021				230,000
Thereafter				1,461,032,000
Long-term Debt Before Unamortized Discount				2,008,954,000
Total				1,990,649,000
Other Long-term Debt, Current				380,948,000		$ 9,974,000
Line of Credit, Maturing August 11, 2021 [Member]
Aggregate borrowings under the amended facility						325,400,000
Unamortized Debt Issuance Expense						3,400,000
Maturities of Long-term Debt [Abstract]
Total						322,000,000.0
Line of Credit, Maturing September 17, 2024 [Member]
Unsecured revolving credit facility, amount								$ 1,000,000,000.0
Line of Credit Facility, Remaining Borrowing Capacity				830,400,000
Letters of credit issued and outstanding				$ 11,000,000.0
Interest rate terms under amended senior unsecured revolving credit facility				The interest rates on the Eurocurrency Rate loans are based on the Eurocurrency Rate at the time of borrowing, plus a percentage spread based on the credit rating of the Company's debt. The interest rates on the US Dollar Base Rate loans are based on the US Dollar Base Rate at the time of borrowing, plus a percentage spread based on the credit rating of the Company's debt. The base rate is the higher of (i) the Federal Funds Rate (as defined in the credit agreement) plus 50 basis points (ii) the rate of interest in effect for such day as publicly announced from time to time by Bank of America as its "prime rate," or (iii) the Eurocurrency Rate plus 1.00%. The Eurocurrency margin as of 44199 was 101.5 basis points.
Weighted average interest rates under amended senior unsecured revolving credit facility				The weighted average Eurocurrency interest rate as of 44199 was 1.16%, which was the interest applicable to the borrowings outstanding as of 44199.
Aggregate borrowings under the amended facility				$ 158,600,000
Unamortized discount and debt issuance costs				(2,621,000)
Unamortized Debt Issuance Expense				2,600,000
Maturities of Long-term Debt [Abstract]
2017				0
2018				0
2019				0
2020				158,595,000
2021				0
Thereafter				0
Long-term Debt Before Unamortized Discount				158,595,000
Total				$ 155,974,000
Line of Credit, Maturing September 17, 2024 [Member] | Base Rate Option Three [Member] | Line of Credit [Member]
Basis spread on variable rate				1.00%
Line of Credit, Maturing September 17, 2024 [Member] | Eurocurrency Rate [Member]
Basis spread on variable rate				1.02%
Line of Credit, Maturing September 17, 2024 [Member] | Base Rate Option Two [Member] | Line of Credit [Member]
Basis spread on variable rate				0.50%
Line of Credit, Maturing December 16, 2016 [Member] | Eurocurrency Rate [Member]
Description of variable rate basis				Eurocurrency margin
Line of Credit, Maturing December 16, 2016 [Member] | Base Rate Option Two [Member]
Description of variable rate basis				Federal Funds
Other Debt Facilities - EUROIMMUN [Member]
Maturities of Long-term Debt [Abstract]
Long-term Debt, Percentage Bearing Fixed Interest, Amount | €					€ 23.1
Long-term Debt, Percentage Bearing Variable Interest, Amount | €					0.1
Other Debt Facilities - EUROIMMUN [Member] | Fair Value, Inputs, Level 2 [Member]
Maturities of Long-term Debt [Abstract]
Other Long-term Debt | €					€ 23.2		€ 25.7
Other Debt Facilities - EUROIMMUN [Member] | Minimum [Member]
Unsecured senior notes, interest rate percent				1.10%	1.10%
Other Debt Facilities - EUROIMMUN [Member] | Maximum [Member]
Unsecured senior notes, interest rate percent				8.90%	8.90%
Other Debt Facilities - EUROIMMUN [Member] | Euribor Rate [Member]
Basis spread on variable rate				1.50%
Other Debt Facilities [Member]
Unamortized discount and debt issuance costs				$ 0
Maturities of Long-term Debt [Abstract]
2017				14,743,000
2018				4,075,000
2019				2,457,000
2020				1,372,000
2021				230,000
Thereafter				282,000
Long-term Debt Before Unamortized Discount				23,159,000
Total				$ 23,159,000
Other Secured Bank Loan [Member]
Maturities of Long-term Debt [Abstract]
Secured Debt | €					€ 6.1		1.9
Other Secured Bank Loan [Member] | Minimum [Member]
Unsecured senior notes, interest rate percent				1.95%	1.95%
Other Secured Bank Loan [Member] | Maximum [Member]
Unsecured senior notes, interest rate percent				8.94%	8.94%
0.6 Percent Senior Unsecured Notes due in April 2021 [Member]
Interest rate terms under amended senior unsecured revolving credit facility				Interest on the April 2021 Notes is payable annually on April 9th each year.
Unsecured senior notes, interest rate percent		0.60%
Gross proceeds from the issuance of debt instrument		$ 298,700,000
Senior unsecured notes issuance as percentage of principal amount		99.95%
Unamortized discount and debt issuance costs				$ (245,000)
Unamortized Debt Issuance Expense						1,100,000
Debt Instrument, Redemption Percentage Upon Change of Control and Downgrade of Debt Instrument		101.00%
Maturities of Long-term Debt [Abstract]
2017				366,450,000
2018				0
2019				0
2020				0
2021				0
Thereafter				0
Long-term Debt Before Unamortized Discount				366,450,000
Total				366,205,000
Debt Instrument, Unamortized Discount		$ 200,000		16,200		100,000
0.6 Percent Senior Unsecured Notes due in April 2021 [Member] | Fair Value, Inputs, Level 2 [Member]
Maturities of Long-term Debt [Abstract]
Total				$ 366,200,000		334,200,000
0.6 Percent Senior Unsecured Notes due in April 2021 [Member] | Treasury Rate [Member]
Basis spread on variable rate				0.15%
3.3 Percent Ten Year Senior Unsecured Notes due in Sept 2029 [Member]
Interest rate terms under amended senior unsecured revolving credit facility				The 2029 Notes mature in September 2029 and bear interest at an annual rate of 3.3%. Interest on the 2029 Notes is payable semi-annually on March 15th and September 15th each year.
Unsecured senior notes, interest rate percent	3.30%
Unsecured senior notes, face value	$ 850,000,000.0
Gross proceeds from the issuance of debt instrument	$ 847,200,000
Senior unsecured notes issuance as percentage of principal amount	99.67%
Unamortized discount and debt issuance costs				$ (9,404,000)
Unamortized Debt Issuance Expense				6,900,000		7,400,000
Debt Instrument, Redemption Percentage Upon Change of Control and Downgrade of Debt Instrument	101.00%
Maturities of Long-term Debt [Abstract]
2017				0
2018				0
2019				0
2020				0
2021				0
Thereafter				850,000,000
Long-term Debt Before Unamortized Discount				850,000,000
Total				840,596,000
Debt Instrument, Unamortized Discount	$ 2,800,000			2,500,000		2,700,000
3.3 Percent Ten Year Senior Unsecured Notes due in Sept 2029 [Member] | Fair Value, Inputs, Level 2 [Member]
Maturities of Long-term Debt [Abstract]
Total				$ 840,600,000		839,900,000
3.3 Percent Ten Year Senior Unsecured Notes due in Sept 2029 [Member] | Treasury Rate [Member]
Basis spread on variable rate				0.25%
1.875 Percent Ten Year Senior Unsecured Notes [Member]
Unsecured senior notes, interest rate percent			1.875%						1.875%
Gross proceeds from the issuance of debt instrument			$ 492,300,000
Senior unsecured notes issuance as percentage of principal amount			99.118%						99.118%
Unamortized discount and debt issuance costs				$ (6,035,000)
Unamortized Debt Issuance Expense				2,800,000		3,300,000
Debt Instrument, Redemption Percentage Upon Change of Control and Downgrade of Debt Instrument			101.00%
Maturities of Long-term Debt [Abstract]
2017				0
2018				0
2019				0
2020				0
2021				0
Thereafter				610,750,000
Long-term Debt Before Unamortized Discount				610,750,000
Total				604,715,000		552,200,000
Debt Instrument, Unamortized Discount			$ 4,400,000	$ 3,300,000		$ 3,500,000
Euro Member Countries, Euro | Other Debt Facilities - EUROIMMUN [Member]
Maturities of Long-term Debt [Abstract]
Other Long-term Debt | €					€ 13.9		21.3
Euro Member Countries, Euro | 0.6 Percent Senior Unsecured Notes due in April 2021 [Member]
Unsecured senior notes, face value		$ 300,000,000.0
Euro Member Countries, Euro | 1.875 Percent Ten Year Senior Unsecured Notes [Member]
Unsecured senior notes, face value | €									€ 500.0
United States of America, Dollars | Other Debt Facilities - EUROIMMUN [Member]
Maturities of Long-term Debt [Abstract]
Other Long-term Debt | €					17.0		€ 23.8
Long-term Debt, Percentage Bearing Fixed Interest, Amount | €					17.0
Secured Debt | €					4.8
Unsecured Debt | €					€ 12.2
United States of America, Dollars | Other Debt Facilities - EUROIMMUN [Member] | Minimum [Member]
Unsecured senior notes, interest rate percent				1.10%	1.10%
United States of America, Dollars | Other Debt Facilities - EUROIMMUN [Member] | Maximum [Member]
Unsecured senior notes, interest rate percent				4.30%	4.30%